var fruitObj = function(){
	this.alive = [];//bool
	this.x = [];
	this.y = [];
	this.aneNO = [];
	this.l = [];
	this.spd= [];
	this.fruitType = [];
	this.orange = new Image();
	this.blue = new Image();
}
fruitObj.prototype.num = 30;
fruitObj.prototype.init = function(){
	for (var i = 0; i < this.num; i++) {
		this.alive[i] = true;
		this.x[i]=0;
		this.y[i]=0;
		this.aneNO[i] = 0;
		this.spd[i]=Math.random()*0.017+0.003;//[0.003,0.02)
		this.fruitType[i] = "";
	}
	this.orange.src = "./src/fruit.png";
	this.blue.src = "./src/blue.png";
}
fruitObj.prototype.draw = function(){
	for (var i = 0; i < this.num; i++) {
		if(this.alive[i]){
			if(this.l[i] <= 15){//growing
				var NO = this.aneNO[i];
				this.x[i] = ane.headx[NO];
				this.y[i] = ane.heady[NO];
				this.l[i] += this.spd[i] * deltaTime;
				//console.log(this.x[]);
			}else{
				this.y[i] -= this.spd[i] * 6 * deltaTime;
			}
			var pic;
			if(this.fruitType[i] == "blue"){
				pic = this.blue;
			}else{
				pic = this.orange;
			}
			ctx2.drawImage(pic,
				this.x[i] - this.l[i]*0.5,
				this.y[i] - this.l[i] * 0.5,
				this.l[i],this.l[i]);
			if(this.y[i] < 10){	//距离顶部10单位就会死亡
				this.alive[i] = false;
			}
		}
	}
}
fruitObj.prototype.born= function(i){
	this.aneNO[i] = Math.floor(Math.random()*ane.num);
	this.l[i] = 0;
	this.alive[i] = true;
	var type = Math.random();
	if(type<0.3){
		this.fruitType[i] = "blue";
	}else{
		this.fruitType[i] = "orange";
	}
}
fruitObj.prototype.dead = function(i){
	this.alive[i] = false;
}
function fruitMonitor(){
	var num = 0;
	for (var i = 0; i < fruit.num; i++) {
		if(fruit.alive[i]) num++;
	}
	if(num < 15){
		sendFruit();
		return;
	}
}
function sendFruit(){
	for (var i = 0; i < fruit.num; i++) {
		if(!fruit.alive[i]){
			fruit.born(i);
			return;
		}
	}
}